Archive for the ‘Chemistry World Highlights’ Category

Painting the mountains blue

Vera Thoss tells Elinor Richards about her bluebell business and research, using her car in her experiments and analysing whale vomit

Vera Thoss lying in bluebell fieldVera Thoss is an environmental chemistry lecturer at Bangor University, UK. Her research is based on ecological chemistry, which addresses processes mediated through specific compounds within ecosystems and environmental chemistry, which is concerned with the impact of human activities on the environment.

What inspired you to become a scientist?

It all started when I was 13 and I had my first chemistry lesson. I instantly took to the subject and from then my mind was made up. I was also curious and wanted to ’understand the world’.

What attracted you to environmental science?

As a chemist, the choice was between synthetic and analytical chemistry. I chose analytical chemistry because it allows you to follow the environmental fate of natural or man-made compounds. Being allowed to spend time in the woods was a big bonus!

What projects are you working on?

Currently, my group is working on oil pollution, composting and plant-derived products. It seems a bit of a stretch but it is all part of carbon cycling: plants build precious molecules, most of the time these remain intact but may transfer into air, water or soil. Crude oil is the remnants of sunken forests. So in the end, all the chemistry comes from plants photosynthesising and creating complex fragrances, tastes and colours. It is fascinating.

What will be the next big breakthrough in your field?

To chemically separate plant material into multiple useable compounds, with environmentally benign techniques, using as little energy as possible and ideally producing no waste at all.

Which achievements are you most proud of?

My beautiful daughter.  Last year I organised the first ’Plants as Providers of Fine Chemicals’ conference, which was very successful.  I also managed to measure picogram amounts of monoterpenes in three-week-old Scots pine seedlings before they were eaten by slugs.

You own a farm from which you run a business selling bluebells called Vera Bluebell. How did this come about?

I was always concerned about the availability of clean drinking water, and moving to a mountain farm near Snowdon in Wales was a strategic choice (it does rain a lot!). Realising that there was abundance of bluebells on the land was a chance discovery after a fire. I was aware of their unusual chemistry though and that was the starting point for Vera Bluebell. Bluebells are protected, which means a license is needed to work with them. There was a demand for wild bluebells as well. We have now been sustainably managing a wild bluebell population for over six years and it has been an interesting journey. I would love to see a bluebell derived extract being used in a commercial product.

What discoveries have you made during your research on bluebells?

Bluebell seeds have a high oil content and the oil has an unusual composition. Even though this is the first chemical assessment of Hyacinthoides non-scripta oil, the chemistry is not earth-shattering. The ecology aspects gave room for more discoveries, for example we found seed stores on the site, meaning that possibly voles or shrew have collected the seeds for storage. This has never been reported before.

Tell us about your bluebell conservation efforts and how your research can help.

We are hoping to show that bluebell seeds can be a source of fine chemicals. We obtain an oil of unusual composition from the seeds. The residue contains iminosugars, which may be of use in future medicines. I am hoping that the compounds isolated from bluebell seeds will be of commercial value, which in turn means that the conservation of bluebells pays for itself. We are hoping to paint the mountains and woodlands blue again.

You’re involved with projects called BEACON and PROBECO. What are these and what is your role in both projects?

BEACON is all about biorefining, obtaining different compounds from the same plant feedstock. There are different feedstocks investigated in BEACON ranging from perennial rye grass to ivy. My role is to analyse whole plant composition and organise the ’ Plants as Providers of Fine Chemicals ’  conference. The PROBECO project was about the influence of monoterpenes on ecosystem processes in Caledonian Scots pine forests. These are very rare ecosystems. Individual pine trees smell different and the forest served as a study site to investigate the role of specific monoterpenes. I was the scientist analysing the smell of thousands of pine trees and we came up with the chemodiversity hypothesis.

In 2007, you worked with Welsh company Used Tyre Distillation Research to produce novel products from used tyres, in particular oil for fuelling cars. What was your role in the research? I read that your car was used to test the fuel. What was the result?

Again my role was to analyse the products. The oil was a complex mixture and we did see some interesting compounds in it. The tyre oil was noticeably energy dense, giving faster acceleration to the car, which has survived the experiment well!

In 2008, you had an odd request to analyse what was thought to be whale vomit (ambergris) on a North Wales beach. Why is whale vomit so important and what did you find?

I’ve had a few requests for the analysis of beach finds. Ambergris is sought after in the perfume industry, but we have yet to get our hands on some. Most samples were waxes or plastic, which possibly fell overboard, just aged in the sea.

What other odd things have you been asked to analyse?

Another nice in-house example for analysis was to trace a smell in the corridor back to its origin: we sampled air in the corridor outside my office and the terrible smell was found to be due to demolition work going on next door. If it stinks don’t automatically blame the chemists!

What do you do in your spare time?

I love gardening, farming and generally just being outdoors. I am an amateur bee keeper and enjoy spending time with my family.

Read the original article at Chemistry World, or Vera’s recent paper in the journal RSC Advances:

Triacylglycerol composition of British bluebell (Hyacinthoides non-scripta) seed oil
Vera Thoss, P J Murphy, Ray John Marriott and Thomas Wilson
DOI: 10.1039/C2RA20090B

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EPA sets safe dioxin level

The US Environmental Protection Agency (EPA) has released its non-cancer science assessment for dioxins after nearly three decades of delays – to a mixture of responses from stakeholders. This report establishes for the first time a reference dose for dioxin exposure in the US, which could be used for regulation.

The EPA has set its threshold for safe dioxin exposure at a toxicity equivalence (TEQ) of 0.7 picograms per kilogram of body weight per day. That limit could result in tougher cleanup standards for hazardous waste sites, and more stringent limits on the amount of dioxins permitted in drinking water as well as the air.

Piglets

In several international incidents, dioxins have accumulated in pork products via animal feed

The non-cancer risk of exposure to dioxins – toxic chemicals that occur naturally in the environment but can also be released through forest fires, burning your trash in the backyard and certain industrial activities-was last reviewed in the US in the 1980s.

‘Today’s findings show that generally, over a person’s lifetime, current exposure to dioxins does not pose a significant health risk,’ the EPA said. Its actions to reduce emissions from all of the major industrial sources of dioxins, combined with the efforts of state governments and industry, have decreased known and measurable air emissions of dioxins in the US by 90% from 1987 levels, it added.

Although the agency concluded that most Americans have low-level exposure to dioxins, it noted that non-cancer effects of exposure to large amounts of dioxin include developmental and reproductive effects, immune system damage, hormone interference, skin disorders and possibly mild liver damage.

While many in the research and environmental communities praised EPA for finally releasing this crucial part of its dioxin reassessment, the chemical industry was less welcoming. The American Chemistry Council (ACC) called the agency’s final assessment ’scientifically flawed,’ and insisted that it ‘provides no defined public health benefit.’ The organisation further stated that it remains unclear why EPA would set a dioxin exposure level that is three times more stringent than other countries and the World Health Organisation (WHO) when the agency contends that current levels of dioxin do not pose a health concern.

‘We are concerned that their flawed reassessment has led to an overly restrictive standard, and it is going to cause problems down the road because it will be referenced for regulatory action,’ ACC spokesperson Scott Jensen tells Chemistry World.

Judging WHO?

But others such as Stephen Lester, science director for the non-profit Center for Health Environment & Justice in Washington, DC, point out that the WHO has set a dioxin exposure level of 1-4 picograms per kilogram of body weight per day, which is not remarkably different from the EPA level. In addition, Lester notes that the WHO developed its standard in 1998, and a great deal of science has moved forward since that time. He says the EPA dioxin reference dose is based on more recent data.

‘This is another example of how industry will never be happy with what the EPA has done, and this is why it has been delayed by 30 years,’ Lester states.

Arnold Schecter, a professor of environmental and occupational health sciences at the University of Texas in Dallas, agrees that there was very strong opposition from the chemical industry to the EPA dioxin reassessment for decades. ‘That slowed things down repeatedly,’ he says.

But even supporters of the dioxin reassessment, like Lester and Schecter, express concern that the agency has failed to address the increased vulnerability to dioxin exposure of the unborn, as well as breast-feeding infants and adults with immune system problems.

They emphasise that sensitivity varies across the population, and fetuses and nursing children are at greater risk because their organs are still forming. Breastfed infants in particular receive a very large dose of dioxins in the fatty part of the mother’s milk, they argue.

Regarding the concerns of industry and others, the EPA says it is confident. ‘EPA’s dioxin assessment was extensively peer reviewed by outside experts,’ the agency tells Chemistry World. ‘This rigorously peer-reviewed non-cancer assessment updates the science and provides important new information to the public.’

The agency is expected to release the rest of its science assessment for dioxins later this year.

Read the original Chemistry World article here

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Be creative, be inspired, be confident

Gregory KorshinGregory Korshin talks to Michael Smith about his passion for environmental science, literature and languages

Gregory Korshin is professor of environmental engineering at the University of Washington, Seattle, US. His interests include environmental electrochemistry, on-line methods to monitor drinking water quality, advanced wastewater treatment operations and environmental chemistry of radionuclides.

What inspired you to become an environmental researcher?

Before I left Russia in 1991, environmental chemistry became something that appealed to me, largely through my reading of English language journals. I felt that I could apply my knowledge of spectroscopy and electrochemistry to solving environmental problems – it was where my heart was and is, because it addresses what we have done or can do to this world – both good and bad.

Why study water?

Water is common to all environmental systems: ground water and surface water processes, radical processes, atmospheric phenomena and so on. It’s a physical and chemical medium for transport of contaminants, always present at interfaces and a daily necessity for all of us. It’s difficult to imagine any quality of life without safe drinking water and sanitation and this drives research, engineering and politics too.

What was your most significant early work in this field?

We discovered simple, frequently linear correlations between changes in absorbance of organic substrates reacting with chlorine and levels of diverse halogenated products formed as a result. Many such compounds are deleterious to health and need to be controlled. We used differential absorbance spectroscopy to probe some of these processes in drinking water and wastewater. We are now measuring fluorescence of natural waters – a beautiful spectroscopic phenomenon that is of interest to many in the environmental community.

Heavy metals are another interest, especially copper and lead in drinking water and using x-ray absorbance spectroscopy to examine the chemical nature of these metals in complex environmental systems.

How far has research on removing contaminants from water progressed?

Water purification is a hugely important and diverse area. Disinfection with chlorine was introduced in Victorian times. When it comes to saving millions of children from waterborne diseases, the Victorian technologies are still very effective.

In the west, we frequently deal with very low concentrations of diverse chemical contaminants that may or may not affect health immediately. In drinking water consumed in developing countries, microbial contaminants determine whether you live or die within hours. Effective, cheap and readily available technologies to control these are important.

Recent developments in water treatment include solar-driven approaches. Their success is tremendously important since they are truly renewable technologies. A range of new materials for water treatment applications are being developed including nanomaterials for removal of trace-level contaminants such as arsenic, but further work is needed. Desalination of sea water is becoming increasingly important.

What’s the next big challenge?

One of several is how to clean contaminated groundwater. This is an incredibly important resource and once a groundwater aquifer has become contaminated, it is very difficult to clean it up. There is currently rapid depletion of erstwhile abundant aquifers.

Trace level contaminants are another important area. There are hundreds of compounds ranging from ibuprofen or synthetic musks to pesticides, cancer drugs and birth control agents. There are currently several views concerning their assumed or documented effects. One hypothesis relates the increased incidence of autism with exposures to such chemicals. Some data indicates that while these compounds may not be so important for adults who have relatively robust endocrine systems, this may not be the case during foetal development or in children.

Many contaminants are endocrine disruptors and their effects on wildlife are very complex and potentially dangerous. Unusual sex changes in fish and invertebrates are observed in rivers without obvious anthropogenic influence, as in many English rivers, as well as in the presence of wastewater effluents, as in the Potomac River in the US. From an ecological point of view, these effects need to be understood, monitored and controlled.

Sometimes we don’t even know what we need to look for. This is because many compounds have not been identified, or cannot be identified because they are part of complex mixtures that cannot be broken down into individual components. These trace contaminants occur at nanogram, or picogram, per litre levels and still induce biological effects. The progress in analytical instrumentation to discover these contaminants has been nothing short of spectacular. Yet, it is still very difficult and expensive to do these studies.

If trace level organics can induce or influence disease in humans or affect life expectancy then this is hugely significant. Already documented effects on fish mean that wastewater needs to be treated more thoroughly than it is done now. However, this should not be viewed as an unwanted complication because wastewater can also be a resource. Phosphorus and ammonia, for example, can be recovered from wastewater and reused as fertiliser.

Which historical character would you most like to meet?

There are several. I have always had tremendous respect for the French tradition of thought. As our Russian poet Pushkin said – that ’sharp Gallic reason’. I admire Laplace and Lagrange who were 18th century French mathematicians and physicists. They were extraordinarily smart people and the culture of science in France then (and now) produced many like this. Joseph Fourier is another one. He created, among other things, a very beautiful mathematical apparatus to analyse very complex phenomena in elegant terms.

Another character that I like a lot is James Clerk Maxwell. His ability to synthesise what relatively little was known at that time about electromagnetism and produce a spectacularly concise set of equations that have been used ever since is astonishing.

So what would your message to a young and aspiring graduate student be?

Be creative, be inspired, be confident. But, ultimately, it is intellectual thirst and curiosity that determines how far one will go.

If you weren’t a scientist, what would you be?

That’s a tough question. It’s a little funny to think about this now but when I was a teenager I was considering a career in the military. I’m not regretting that I didn’t take that up, but it could have been. Actually I do love learning. I love linguistics and history. Linguistics is a great science. I have always been drawn to it. It seeks and finds commonalities in different systems. It has to do with trying to determine what human mind is. I also love optics and light. One of the most fantastically beautiful things in my graduate studies was that I got to design, make and use interesting optical cells, light sources and detectors, and so on. If I hadn’t become a scientist then I would have moved into optical engineering or design.

What do you do when you’re not working?

I dabble in abstract painting. I study languages all the time (at the moment Farsi and Portuguese). I read a lot, often classic Russian poetry and prose. I truly love classic Roman, Italian and French literature. I love history and art. I like socialising with friends and relatives – I have many relatives, we’ve been blessed that way. Travel too: I’ve been to many countries but it’s still not enough.

Read the original Chemistry World article here

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Arctic biting back over mercury pollution

In the Arctic, there are high concentrations of mercury in humans and animals and scientists are investigating how the mercury got there. Mercury has a tendency to accumulate in organisms and bio-magnify (increase in concentration) up through the food chain, so monitoring its levels in the environment is important. In previous investigations, polar bear organs, such as the liver, kidney, hair and blood have been analysed for mercury content, but the results can be inaccurate because soft tissues change throughout the lifetime of the animal.

Polar bear skull

Polar bear teeth from the Natural History Museum at the University of Oslo, Norway, were used as biotracers of temporal changes in mercury pollution exposure. © Aurore Aubail

Now, Aurore Aubail from the National Environmental Research Institute, Denmark, and colleagues from France and Norway, have investigated the temporal trends of mercury using polar bear teeth. Teeth are seen as better materials to use, as contrary to soft tissues, the tooth is not remodelled throughout its life and the mercury is not remobilised.

‘Lots of teeth of various Arctic species are stored in natural history museums of Nordic countries and these institutions are a mine of environmental pollution archives,’ says Aubail. ‘Their collections often go back 100-200 years, which allow researchers to establish time trends of pollutants. Working with these polar bear skulls was really exciting, but extracting the teeth was quite a hard task. It even involved a toolbox!’

The team collected teeth samples from 87 polar bear skulls from the Natural History Museum at the University of Oslo, Norway. They analysed mercury concentrations by solid sample atomic absorption spectrophotometry and the relative abundance of carbon (13C/12C) and nitrogen (15N/14N) stable isotopes by an isotope-ratio mass spectrometer to provide information about potential changes in feeding habits or habitats for polar bears.

The results showed that there has been an overall decrease in mercury concentrations in the Arctic over the last 50 years, which supports earlier results found in polar bear hair from Greenland and human deciduous teeth from Norway. The results from the stable isotope ratios eliminated variations in the feeding or foraging habits as a potential explanation. As the mercury emissions are not sourced from the Arctic, another possible cause is a decrease in the source of the mercury emissions from Europe and North America.

‘Polar bears are an especially useful species for the biomonitoring of contaminants,’ says Sara Moses, an environmental biologist from the Great Lakes Indian Fish and Wildlife Commission, US. ‘Because they are long-lived and sit atop the Arctic food web, they are particularly susceptible to accumulating high levels of mercury in their tissues. As a result, mercury levels in polar bears integrate exposure throughout the food web and provide important information about lower trophic levels as well.’ She adds that teeth are useful monitoring tools because bone is more readily available than soft tissues in many archives and provides a matrix that is relatively stable over time.

Aubail hopes that further investigation into the use of polar bear teeth to study mercury will continue as it is ’still a valuable material that allows us to study long term trends of pollutants’.

Interested? Read Andrew Shore’s full Chemistry World article here or download the JEM paper:

Temporal trend of mercury in polar bears (Ursus maritimus) from Svalbard using teeth as a biomonitoring tissue
Aurore Aubail, Rune Dietz, Frank Rigét, Christian Sonne, Øystein Wiig and Florence Caurant
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10681C

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Devices to help miners breathe easier

New field-portable infrared (IR) devices that can measure mine workers’ exposure levels to silica in coal dust have been designed and tested by scientists in the US.

The inhalation of microscopic particles of crystalline silica is a serious health hazard, and causes a debilitating, and often fatal, condition called silicosis. Miners in particular are at risk of developing this condition.

Currently, samples collected at the field site are sent to a laboratory for testing, often taking weeks to get the results. This time delay between collection and analysis reduces the usefulness of the results in modifying workplace practices to decrease exposure. As the mining workplace is often moving into new geological strata, with changing levels of silica, a faster turnaround in silica measurements is a priority.

Arthur Miller at the National Institute for Occupational Safety and Health, Spokane, and colleagues have based their work on the successful personal dust monitor (PDM), which measures workers’ exposure to coal dust. However, the PDM does not measure silica levels specifically.

Hands holding coal

Coal miners are at risk of developing silicosis by inhaling microscopic particles of crystalline silica in coal dust. © Shutterstock

‘It is our intent to develop a field-portable method for measuring silica that miners can use to get immediate feedback regarding their exposure. Such a device could be used to inform immediate adjustments to the mining process that reduce silica exposures, thereby reducing disease and death due to silicosis,’ says Miller.

The challenge was to design an IR device that could measure quantities of silica at low levels, and get around the interference from other minerals in the air, especially kaolin, using a correction scheme. Two IR devices were tested, one using FTIR spectrometry, the other variable filter array (VFA) IR spectrometry. When compared with the current, laboratory-based method, the FTIR data was found to be comparable.

‘The originality of the approach is to bring an analytical method near to the workplace that enables immediate exposure control in order to prevent occupational lung diseases of miners,’ comments Peter Görner, head of the aerosol metrology laboratory at the National Research Institute on Occupational Safety and Health, Vandoeuvre, France.

The next step is to test the feasibility of the new devices as end-of-shift methods of data collection. Work is still needed to determine the best ways of gathering and handling samples, as well as error analysis, but the hope is that this new technology will one day provide immediate results that can allow miners to adjust the mining process to reduce silica exposure.

Interested? Read Rebecca Brodie’s full Chemistry World article here or download the JEM paper:

Evaluating portable infrared spectrometers for measuring the silica content of coal dust
Arthur L. Miller, Pamela L. Drake, Nathaniel C. Murphy, James D. Noll and John C. Volkwein
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10678C

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Bomb squad plants

Scientists from Puerto Rico have discovered plants that are not only resistant to high levels of TNT but can remove it completely from aqueous media in under 48 hours.

The explosive trinitrotoluene (TNT) is a persistent contaminant that is toxic and mutagenic, and thanks to its use in over 80 per cent of the landmines worldwide, it can be found throughout the globe at military sites and war zones alike.

Caribbean plant and stick of dynamite

Military sites and war zones contaminated with TNT could be cleared by tough Caribbean plants

Samuel Hernández-Rivera and co-workers at the University of Puerto Rico-Mayagüez investigated the ability of three Caribbean plants – Rubia tinctorum, Lippia dulcis and Spermacoce remota – to remove TNT. Plantlets of each were added to flasks containing solutions of TNT and samples were taken at timed intervals for high performance liquid chromatography analysis, with a flask containing just the TNT solution used for comparison.

R. tinctorum and L. dulcis removed nearly 100 per cent of the TNT from the liquid medium, showing a roughly 10-fold increase in the rate of TNT removal compared to loss by evaporation in the control flask. What is even more significant is that S. remota, under identical conditions, can completely remove TNT from the media in under 48 hours.

Hernández-Rivera and his colleague Fernando Souto-Bachiller say that the main mechanism for TNT removal from the media is via adsorption through the roots, but once adsorbed, S. remota seems to have a different mechanism of action. They say that this result was initially attributed to either ‘a possible enzyme exudate, which would then be responsible for TNT degradation, or a symbiotic relationship between the plant roots and a persistent microorganism, fungus or bacteria.’ Future work within the group will involve isotopically labelling TNT to investigate the enhanced behaviour of S. remota.

Tomás E. Macek from the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Czech Republic, says that the work deals with an ‘important topic and that detoxification of contaminated sites is a global problem’, but ‘there is much to be done to allow effective exploitation in the field’.

Hernández-Rivera says that ongoing experiments are focused on using the plants in TNT contaminated soil, and although ‘physical and biochemical processes in soils are much more complicated’, initial results look promising.

Interested? Read James Anson’s full Chemistry World article here or download the JEM paper:

TNT removal from culture media by three commonly available wild plants growing in the Caribbean
Sandra N. Correa-Torres, Leonardo C. Pacheco-Londoño, Eduardo A. Espinosa-Fuentes, Lolita Rodríguez, Fernando A. Souto-Bachiller and Samuel P. Hernández-Rivera
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10602C

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Cleaning up water

Dion Dionysiou is professor of environmental engineering and science at the University of Cincinnati, US, where he works on advanced oxidation technologies for water treatment.

What inspired you to go into science?
After my national service in the army I studied chemical engineering at the National Technical University in Athens, Greece. I enjoyed both the engineering and chemistry courses. I also worked hard to improve my English at this time because I really wanted to go to the US for graduate studies.

I gained a place at Tufts University, Massachusetts, and my masters thesis focused on developing de-icing materials for roads, particularly crystallisation of environmentally friendly de-icing solutions, for example, calcium magnesium acetate. I then worked for W. R. Grace & Co. to develop masonry materials and later went on to the University of Cincinnati, Ohio, where initially my PhD dealt with developing perovskite materials for gas separations and advanced materials for energy applications.

What made you switch to studying water?

I always wanted to work with water related issues, ever since being a child in Cyprus where there was a major issue of water scarcity. When I was quite young, people in my small town in Cyprus had to get water each day from fountains in their neighbourhoods because we didn’t have a direct supply to the house. This experience has made me especially interested in water conservation and water supply.

Why did you focus on advanced oxidation technologies in water treatment?
During my PhD I moved into the field of environmental engineering and studied photocatalysis for water purification, which was funded by the Center of International Research for Water and the Environment (Centre International de Recherche Sur l’Eau et l’Environnement) of ONDEO Services. Around this time, in 1996, there was an international conference on advanced oxidation technologies, which took place in Cincinnati. Photocatalysis was one of the processes covered, along with various other methods that interested me. I was a student helper that first year and every year after that I aimed to present some of my work at that particular meeting.

Within your field, what is the next big thing?
Advanced oxidation is an area of tremendous growth as a means of treating wastewater for reuse in irrigation or even for human consumption. Singapore is a very good example of where such technologies are being used. Here in southern California, membrane microfiltration is one approach. Reverse osmosis and combined UV-hydrogen peroxide treatments are also used.

Water availability in developing countries is another very important topic. Many communities don’t have access to clean water and large numbers of people die from water borne diseases. Water forms an integrated cycle: wastewater when discharged into rivers or lakes ultimately becomes a source of drinking water. So clearly the content of pharmaceutical and other compounds in water must be regulated. Eutrophication of water resources, which leads in many cases to the formation of harmful algal blooms and associated cyanotoxins, should also be eliminated or at least minimised.

Another developing area concerns the analytical methods needed to detect compounds of emerging concern. New compounds are being introduced into the water system and their biological and chemical breakdown products need to be identified and their toxicity understood.

There are also new materials being developed for use in water treatment. Nanomaterials can be involved in removal of pollutants from water, but may in turn enter the water themselves. There is a need to predict and monitor what happens to these materials. Photocatalytic materials, for example, have nano components that can leach out and the effects of pH and other factors on these in the complex matrix of water need to be understood in order to see the whole picture.

What advice would you give to a young person who is considering a career in science?

I think there are tremendous opportunities with respect to a career in science and engineering and I would encourage young people to explore these opportunities. Discovery is a beautiful thing. I would also encourage them to be creative and motivated. I believe young people are smarter than we are, and we should do all we can as educators of the next generation to help provide opportunities for these young people.

What would you do differently if you had the chance?

I would focus more on chemistry. I am a chemical engineer and work on materials for environmental applications, but if I had the chance again I would go deeper into the fundamentals, into basic science, simply because I like it. I enjoy understanding something in depth. For example, in environmental engineering you are often dealing with a very complex system: water and water treatment involve complex interactions – microbes, natural organic matter, chemical oxidants and inorganic chemicals. I enjoy discovering the mechanistic aspects of these interactions.

What I enjoy about engineering is that you can solve problems for humanity. To purify and recycle water is a very valuable thing to do. In Cyprus we have desalination plants but they are expensive and so working to develop better membranes to deliver water recycling at reduced cost is good to do. When scientists and engineers work together, that’s great.

When you’re not doing science and engineering, what do you like doing?
I enjoy my involvement with publishers and I take my editorial and refereeing responsibilities very seriously. I also love watching soccer, particularly European soccer – I’m a big fan. I don’t play soccer anymore, but I have two daughters who both play here in the US.

For the original interview article see Chemistry World

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Firefighters need more protection from chemical fumes

A study by US scientists has highlighted the need for new respirators for firefighters.

Although firefighters usually wear self-contained breathing apparatus (SCBA) when tackling structural fires, this is a much less common practice when dealing with vehicle fires. The potential health risk from vehicle fire fumes is considered minimal, as the fires are outdoors and are usually extinguished rapidly. In addition, SCBA is cumbersome to wear and takes a long time to put on.

However, Kenneth Fent and his team at the US Public Health Service and the National Institute for Occupational Safety and Health, Cincinnati, have shown that firefighters are actually exposing themselves to almost ten times the acceptable level of 75 volatile organic compounds, including benzene, acetonitrile and acetone.

 

The measure of risk to a mixture of chemicals was found to be 9.2 times the acceptable amount

Link to journal article
Assessing the risk to firefighters from chemical vapors and gases during vehicle fire suppression
Kenneth W. Fent and Douglas E. Evans, J. Environ. Monit., 2011
DOI: 10.1039/c0em00591f

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Hope on the Horizon for ecological recovery

Hope may be in sight for the Deepwater Horizon clean up operation as Spanish researchers show the rapid recovery of wild mussel populations following a similarly disastrous oil spill.

In November 2002, the tanker Prestige split in two, disgorging over 60 000 tonnes of oil into the Atlantic Ocean. The Galician coastline, Europe’s largest producer of mussels, was one of the worst affected areas. Miren Cajaraville led a team at the University of the Basque Country, Leioa, to assess the impact of the spill on the reproductive capabilities of wild mussel populations.

Mussels are commonly used as a gauge of marine pollution levels as they are inactive and do not move to feed, so accumulate high levels of contaminants from their environment. Cajaraville monitored the levels of a protein that control the development of sex cells in females along with other indicators of abnormality, such as premature cell death and abnormal reproductive organ development to determine the effect of the oil-contaminated waters on the mussels.

Mussels are commonly used as a gauge of marine pollution

Read the full story here
Link to journal article
Effects of the fuel oil spilled by the Prestige tanker on reproduction parameters of wild mussel populations
Maren Ortiz-Zarragoitia, Larraitz Garmendia, María Carmen Barbero, Teresa Serrano, Ionan Marigómez and Miren P. Cajaraville
J. Environ. Monit., 2010, DOI: 10.1039/c0em00102c

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Monitoring radicals in water

A sensitive probe to monitor hydroxyl radicals in water has been developed by a team of Swiss and US scientists.

Hydroxyl radicals are high-energy oxidants that are important in the biology of ageing and radiation damage, as well as in environmental chemistry. In natural water systems, the radicals are produced photochemically from nutrients such as nitrates or nitrites and pollutants such as dissolved organic matter. And accurately measuring hydroxyl radical concentrations can help understand the fate of pollutants.

Current hydroxyl radical probes, such as benzoic acid, often have limited sensitivity, require long irradiation times or high concentrations of the probe, which can affect the sample. Now Kristopher McNeill at the Swiss Federal Institute of Technology (ETH) in Zurich and colleagues at the University of Minnesota in Minneapolis have discovered that terephthalate is a more sensitive probe for hydroxyl radicals in aquatic environments.

Terephthalate picks up an OH radical to form fluorescent hydroxyterephthalate

Click here to read the full story

Link to journal article:
Terephthalate as a probe for photochemically generated hydroxyl radical
Sarah E. Page, William A. Arnold and Kristopher McNeill, J. Environ. Monit., 2010, 12, 1658
DOI: 10.1039/c0em00160k

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